Volkswagen did not name a successor, but said proposals on management appointments would be made to a full board meeting on Friday.
Porsche chief Matthias Mueller, Audi chief Rupert Stadler and the head of the VW brand, Herbert Diess, are seen as the front-runners to replace Winterkorn, three people familiar with the matter said. Mueller is seen as the favourite among the three due to his years of experience within the group, two of the people said.